Combining ability of white corn genotypes with two commercial hybrids


White corn is a special type of corn used to make «canjica», a dish appreciated in many regions in Brazil. However, there is a shortage of scientific information, genetic statistical estimates for breeding programs and white corn cultivars for producers to produce grits. The objectives of the present study were to assess two groups of white corn genotypes in a partial diallel cross for the main agronomic traits, estimate the combining ability of the parents and identify promising white corn hybrids for yield and grits quality. The fourteen topcross hybrids obtained from a partial Diallel (2 x 7), using seven genotypes and two commercial testers of the white maize (IPR 119 e IPR 127). The resulting hybrids and the two commercial controls were assessed in the 2011/2012 in the experimental center Agronomic Institute in Campinas (IAC) in growing season at the in Campinas and Tatuí, São Paulo state, Brazil. A randomized block design was used with four replications. The traits assessed were male flowering (MF), female flowering (FF), plant height (PH), ear height (EH), percentage of broken and lodged plants (Ld + Br) and grain yield (GY). There were two treatments for all the traits assessed in the two locations and some hybrids presented higher mean production than the commercial controls. The P7, P1, P3, and P2 genotypes presented the best general com¬bining ability for all the traits assessed. The best estimates for specific combining ability were observed in the P6 x P9, P2 x P9, and P7 x P8 hybrids, indicating dominant loci systems in the genetic control of the traits PH, EH and GY.


Zea mays L; topcross hybrids; diallel cross and grits corn

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